D.C. Code § 9-918
All proceeds from the sale of bonds and revenues derived from the bonds received pursuant to the provisions of this chapter shall be considered to be trust funds to be held and applied solely as provided in this chapter. The Authority may, in the resolution authorizing the bonds or in the trust agreement securing the bonds, provide for the payment of the proceeds of the sale of the bonds and the revenues of the Authority to a trustee, which may be any trust company or bank having the powers of a trust company within or without the District, which shall act as trustee of the funds, and hold and apply the funds to the purposes of this chapter, subject to any regulations this chapter and the resolution or trust agreement may provide. The trustee may invest and reinvest the funds in securities as may be provided in the resolution authorizing the bonds or in the trust agreement securing the bonds.
D.C. Code § 9-918